How Fast Should Bilateral Stimulation Be? Speed, Intensity and Set Length Explained

One of the most common questions people ask about bilateral stimulation, whether they are an EMDR therapist setting up a session or someone using tappers at home, is deceptively simple: how fast should it be? The short answer is that most tactile bilateral stimulation in EMDR settings runs at roughly one alternation per second, and that faster is generally used for processing work while slower is generally used for calming and resourcing.

That single sentence hides a lot of nuance. Below is what published research actually shows about speed, what standard EMDR protocols specify about set length, how speed differs from intensity, and how the main tactile devices on the market let you control these settings.

What speed does bilateral stimulation normally run at?

In clinical descriptions of tactile bilateral stimulation, the therapist taps alternately on the back of the client's hands, and the frequency of that alternation varies around 1 Hz, which is roughly one tap per side per second. Vibrating alternating hand devices are used to reproduce the same rhythm without the therapist doing it by hand.

That 1 Hz figure is a reference point rather than a rule. Practitioners adjust up or down depending on what phase of work they are in and how the person in front of them responds. This is exactly why adjustable speed is a meaningful feature on a device rather than a marketing bullet.

What the research says about faster versus slower

The most directly relevant study is a 2015 experiment published in Frontiers in Psychiatry, titled "Speed Matters". Seventy-two participants recalled aversive autobiographical memories under different conditions, and recall combined with fast eye movements produced images that were less emotional, less vivid, and harder to retrieve than recall with slow eye movements or recall alone.

Eye movements at 1.2 Hz produced more working memory taxation, lower image vividness, and greater difficulty retrieving the image than eye movements at 0.8 Hz or 1.0 Hz.
Source: Speed Matters, Frontiers in Psychiatry (2015)

Two important caveats. First, that study used eye movements, not tactile taps, so the findings do not transfer automatically to tappers. Second, it was a laboratory paradigm with non-clinical memories, not a clinical trial. It tells us something about mechanism, not about outcomes at home.

On the physiological side, a study published in BJPsych Open in November 2025 compared visual and tactile bilateral stimulation in twenty women with PTSD and twenty matched controls. Both modalities increased total frontal EEG power and decreased peripheral physiological activation, and the effects held regardless of whether the recalled memory was stressful or neutral. The authors frame this as support for the idea that bilateral stimulation engages top-down cortical regulation. More research is still needed, as they note themselves.

If you want the broader evidence picture, we covered it in more depth in Is Bilateral Stimulation Backed by Science? and compared modalities in Tactile vs Visual vs Auditory Bilateral Stimulation.

Fast and slow do two different jobs

In EMDR therapy, speed is not a single dial you set once. Francine Shapiro's 2018 edition of the standard EMDR text describes fast bilateral stimulation for processing work, and slower, shorter sets for installing positive resources such as a calm place. Resource development and installation is commonly described using slow taps in short sets of roughly four to six passes.

The practical takeaway for anyone using tappers outside of therapy is that the fast, long-set configuration belongs to structured trauma processing with a trained clinician. For self-guided use at home, the slower and gentler end of the range is the sensible default.

Speed is not the same as intensity

Speed is how often the stimulation alternates from one hand to the other. Intensity is how strong each individual pulse feels. They are independent settings, and confusing them is the most common reason people say a device feels wrong.

• Too intense, right speed: the rhythm feels correct but each buzz is distracting or startling. Lower the intensity, keep the speed.
• Right intensity, too fast: it feels agitating or busy rather than settling. Slow it down before touching intensity.
• Barely noticeable: raise intensity first. A pulse you have to concentrate to feel is doing less than one you can notice with your eyes closed.

A useful rule of thumb: the stimulation should be clearly noticeable but never uncomfortable. You are aiming for something you can forget about after a minute, not something you keep bracing against.

How different devices let you adjust these settings

Devices differ substantially in how granular their controls are. Some offer preset speed steps, some use physical knobs on a wired controller, and some move the controls into a phone app. Here is how the main tactile options compare on control alone.

There is no single winner here. The wired consoles from TheraTapper and NeuroTek give a therapist a physical dial they can turn mid-set without looking at a screen, which many clinicians genuinely prefer. TouchPoints keeps things simple with three presets, which is fine if one of the three happens to suit you. Priced at $189 and up, it sits above ALMA at $139.

ALMA takes the app-controlled route: speed, intensity, light and session duration are all continuous settings in the app rather than fixed presets, which makes it easy to find a rhythm and then keep returning to it. The tappers themselves are food-grade silicone, soft and rounded in the palm, app-controlled, with IPX7 water resistance, USB-C charging and more than three hours of battery.

Notes for EMDR therapists

If you are running sessions, the practical question is not just what speed to use but how quickly you can change it. Two patterns come up repeatedly among clinicians who use wireless tappers.

1. In session: set a slower, gentler configuration during preparation and resourcing, then a faster configuration for processing work, and switch between them without unplugging or rearranging cables.
2. Between sessions: some therapists let clients keep a slow, low-intensity setting for self-regulation practice between appointments, framed clearly as grounding rather than processing.

One thing that is not possible yet with most consumer tappers is remote control by the clinician during an online session. A videoconference feature that would let a therapist control a client's tappers remotely is on the ALMA roadmap and is coming soon, but it does not exist today. Until then, remote sessions rely on the client adjusting settings themselves, which we discussed in our guide to bilateral stimulation in telehealth EMDR sessions.

Frequently asked questions

Is there one correct speed for bilateral stimulation?

No. Around 1 Hz is the frequently cited reference for tactile bilateral stimulation, but protocols deliberately vary speed by task, and individual comfort is a legitimate reason to adjust. A speed that feels agitating is not the right speed, regardless of what a study used.

Does faster always work better?

Not for every purpose. The laboratory finding that faster eye movements reduced memory vividness applies to processing aversive memories. For calming and resource work, EMDR protocols describe slower and shorter sets. Faster is a tool for a specific job, not a general upgrade.

How long should a session at home be?

Many people using tappers for wind-down settle on something in the range of 5 to 20 minutes at a slow, comfortable setting. Devices with a duration timer make this easier because the session ends on its own. Start short, notice how you feel, and adjust from there.

What speed should be used with children?

Whether a tapper is appropriate for a particular child is a decision for a qualified professional who knows them. It isn't something we can advise on, and we don't make safety claims about children's use of our product.

The practical summary

Start near one alternation per second. Use a slower, gentler setting for calming and self-regulation, and leave faster processing configurations to structured work with a trained EMDR therapist. Treat intensity as a separate dial from speed, and adjust one at a time. Above all, choose the setting that feels settling rather than the one a study used, because the two are not always the same number.

If your current device only offers a few fixed presets, the ability to fine-tune speed, intensity, light and duration continuously is the single feature most likely to change how usable it feels day to day. That is the design choice behind the ALMA app-controlled tappers, which ship with a 30-day money-back guarantee and free US shipping.

ALMA tappers are general wellness devices inspired by EMDR therapy. They are not medical devices and are not intended to diagnose, treat, cure or prevent any condition. If you are working with trauma, please do so with a qualified mental health professional.